Wireless telegraphy.



No. 67|,406. Patented Apr. 2, |90I. H. SHOEMAKER. WIRELESS TELEGRAPHY.

(Application led Jan, 1T, 1901.)

(No Mudel.)

UNITED STAT-ES PATENT OFFICE.

HARRY SI-IOEMAKER, OF PHILADELPHIA, PENNSYLVANIA, ASSIGNOR OF ONE-IIALF TO MARIE V. GEHRING, OF SAME PLACE.

WIRELESS `TI-L'mRAIPHY.

SPECIFICATION forming part of Letters Patent No.

671,406, dated April 2, 190i.

Application filed January 17, 1901. Serial No. l3,631. (No model.)

To a/ZZ whom it may concern:

Be it known that I, HARRY SHOEMAKER, a citizen of the United States, residing at Philadelphia,county of Philadelphia,State of Pennsylvania, have invented certain newand useful Improvements in Wireless Telegraphy; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

My invention relates to new and useful improvements in wireless telegraph systems, and has for its objects to provide a system ernbodying a novel form of emitter or oscillator andV means for increasing the eifective force of the ether-waves at the transmitting-station and a simple and efficient form of coherer and restoring mechanism at the receiving-station in connection with means to produce dots and dashes in accordance with the Morse code at the receiving instrument.

The preferred form of my invention is illustrated in the accompanying drawing, representing a system having a transmitting and receiving station.

In the drawing two stations are represented, one having a transmitting apparatus X and the other a receiving apparatus Y; but it is to be understood that in the operative commercial arrangement of the system each station will be equipped with both transmitting and receiving apparatus.

The transmitting apparatus comprises an ind uctorium or Ruhmkorf coilA, the primary of which is energized by a suitable battery or current source Bin circuit The interrupter comprises the' vibrating armature A and adjustable stop A2, such as are ordinarily employed. In series with the primary is an ordinary sending-key C, and in a derived 'circuit with the interrupter is a condenser D. The effect of the condenser D is to reduce sparking at the interrupter and produce a more rapid and very uniform action of the induction-coil.

To the secondary of the induction-coil is `connected an external circuit n, terminating in two balls or spheres II', preferably of brass, adj ustably mounted on an insulating-base S. The balls I and I respectively are' connected to an aerial conductor-plate H and a ground Gr.

The oscillator or emitter comprisesa tube F, of glass or other non-conducting medium, which is mounted at its ends in supports F', connected to the base S. A tight joint is secured between the tube F and its supports by packings or gaskets F2. Adjustably mounted in the supports are two conducting'rods E E, each of which has secured to it an external metal ball E2 anda smaller metal ball E. The balls E E' are of a diameter considerably less than the bore of the tube and occupy positions in proximity to each other to provide a slight air-gap between them. The tube F is filled with air or, preferably, a non-corrosive gas under heavy pressure to provide a suitable dielectric medium for the spark-gap between the balls E. I-Ieretofore it has been the practice to employ vaseline, oil, or the like material betweenthe balls; but I have found that an oscillator so constructed is sluggish in action and that after a spark has passed between the ballsconsiderable time must elapse before another discharge will pass the oil dielectric, thereby rendering the action of the transmitting apparatus slow. This effect is apparently due to carbonization of the oil between the balls and the formation of a lowpressure gaseous envelop about the sparkingterminals. Byemployingagaseousdielectric under heavy pressure this objectionable retardation in the oscillator is eliminated, as the high-tension gas always preserves a uniform medium inthe spark-gap, thereby greatly increasing the rapidity and regularity of action of the emitter.

The receiving apparatus (illustrated at the right of the drawing) comprises an aerial conductor-plate II', connected by a conductingwire Zthrough a detector or coherer to earth at G'. Said coherer consists of an evacuated tube K, provided with two L-shaped blocks of insulating material K', having in their contiguous inner faces plates of conduct-ing material K2, preferably of silver, of less height than said faces. The space between the blocks is filled to the height of the conducting-plates with metal filings .K3 of the character usually employed in coherers. Each of said plates is connected to the wire l, which IOO A ball K4, of magnetic material, occupies the the air-gaps between the vball-terminals ofthe sribed. City of thed'ischa'rge 42110 'gaseous diel, 6s

"nottarnished or corroded, l'even-"u'x1'der long-i --mally broken' at the back contact c2 and is a specially-trained operator.

:corrosive gas'the surfaces of the balls E are' is sealed in the opposite ends of the tube K.

space above the iilings and"'normally rests on the edges of the blocks K. This ball, together with the electromagnet M, hereinafter described, forms an automatic tapper or de-f cohering device.

Connected in derivation with the coherer and circuitZ is a main circuit 0, containing a battery B anda relay R, having a normally-2` retracted armature a. Connected with said armature a andthe front contact c of said relayR is a circuit p, having a battery B2 and an electromagnet 'm in series. In derivation oiA circuitp is a circuit p', including the coil r of a compound relay R. Connected with the front contact c and one side of the circuit p is a circuit 2, which includes in series the other coil r of the compound relay R' and a condenser D. Said relay R controls an armature a', which is normally` held against back contact c', thereby closing a circuit s, containing a battery Bs and a relay R3. Said relay Ri controls an armature a, and normally holds it away from the back contact ci against the tension of a retractile spring.

A Morse sounder or equivalent signaling instrument Sis connected in circuit t with an 4 energizing-battery B4, which circuit is n'orclosed when the armature a? rests on contact c2; Heretofore it has been diilicult to produce simple dots and dashes at the receiving-station, and it has been customary to represent a dash at the-receiver by a series of impulsesand a dot by a less number of'impulses. This expedient resulted in a rapid flickering or' buzzing ofthe zmoving member of the re-A ceiver, which made it necessary to permit the member to come to rest after each character.; transmitted and also required theserv'ice of'` Bythe arrangevment described above I 'am enabled to em-' 'ploy an ordiuarytype of receiver-as', for in; stance, a orse sounderwhich 'produces positive dots and dashes precisely as in or;E dinary telegraphy in accordance with the op' eration of the transmitting-key C.

The operation of the system is 'as follows: The sending-operator mani-pir; lates the key C in accordance with the Morse code and at each make fthe induction-coil A is set in operation, its interru ter'producing a very rapid series of makes and breaksiinthe circuit m,'thereby inducing a rapidly-alternating current in the' secondary. The discharge -from the secondary'takesplace acrossi emitter, resulting in the 'well-known electric oscillations from the aerial plate H, vW'hicliaatre i vradiated into space in waves. As above. der, theintensity, rapidity, and `regu"lar..=

are greatly enhanced by; e tric -under pre' ureri-ngthe tribe F, and 'by' employing an inert l,or "non-,

continued use. Some of the ether-'waves emit-l ted from H are taken up by the corresponding aerial plate H' at the receiving-station Y and carried by the circuitZ to the detector or coherer, which immediately becomes active, allowing the local battery B to operate and '1 energize relay R. The energiz'ation of the said relay draws up armature a, against the contact c, thereby closing the circuit of battery B2 through the magnet M, which attracts the ball K4 in the coherer, which delivers asharp blow on the inside of said tube, thereby causing the particles in the detector to decohere and breakthe circuit of battery B, which deenergizes relay R, and consequently the magnet M, allowing ball K4 to fall. Each impulse received at H will produce a complete cycle of operations just described. Hence to permit the ball K4 and the armature a. to operate with suliicient rapidity to respond to each action of the coherer the movement of both is very small. In addition to the energization of M at each impulse the current from B? passes-by way of shunt-circuit 410 to the coil r of relay R', causing said coil to attract its armature a'. In the regular'practice of the art as heretofore developed this relay R' or its equivalent constituted the receiver or sounder. Hence a dot of the Morse code (indicated at relay R') would consist of a number of rapid clicks of the armature corresponding tothe number of impulses received and a dash would be composed of a relatively greater number-of clicks. It is my purpose to avoid this vibration lof the armature and'cause it `to produce thesimple dot and dash of thecode. When lthe circuit of `B2 is closed at c c, the circuit p of the auxiliary coil r' isv also closed through -the condenser D', and -when the circuit from B2 is broken said condenser discharges 'through circuits p and 10; continuing the energization of coil fr' and holding the armature a' attracted during the inter 'vals between impulses. Relay R 'therefore constitutes a receiver in itself, which responds to the impulses of the transmitter in the aggregate, producing as a short forward stroke f of. the armature'the dot` 4corresponding to a above d. scribed 5 series of impulses and as a prolonged forward stroke the dash which 'I'n order 'to employ an receiver, the additional circuits 's'and t are denergizes relay "'lnitted -and received with 'great rapidity by operators whdare only fami-liar with'tlea tion of the common form-of transmittingand Y,

receiving instruments. l

It will be seen 'that I'have produced a sys-4 tem that 'is more 1rapid and'eillcieut'iujop'e'rast-l tion .any 'heretoforeknown, 'that is pslile transnii results 'from arela tively greater number of impulses. j' t ordinary telegraph- Y 12o provided. .The forward stroke f the armav IOO IIO

o2, thereby energ accordance'with x25. means -the messageor signal mayfbe A'tr'ausg intelligence 1 distances because of the increased-regularity and intensity of the oscillations and the increased sensitiveness of the detector or co'- herer, and that meets the commercial requirement of producing simple dots and dashes at the receiver.

I-Iaving thus described my invention, what I claim, and desire to secure by Letters Patent, is-

l. An emitter of ether-waves, comprising sparking-terminals, and aninclosing envelop of gas under pressure.

2." An emitter of ether-waves, comprising sparking-terminals, and an inclosin g envelop of non-corrosive gas under pressure.

3. Au emitter of ether-waves, comprising a pair of sparkingterminals, and an inclosing casing therefor containing a non-corrosive gas under pressure. v

4. In a transmitter of ether waves, the combination of a current source, having an earthed and an aerial conductor, an emitter between said conductors comprising sparking-terminals, a casing therefor containing a gas under pressure, and means to control said current source.

5. In a transmitter for ether-waves, the combination of a current source having an earthed and an aerial conductor, a sparkingconductor in each of said conductors and an emitter between said sparking-conductors, said emitter comprising sparking-terminals having an inclosing casing containing gas under pressure.

6. In a detector for ether-waves, the combination of a tube containing metallic powder, a circuit through the powder, means carried in said tube for shaking the powder, and means to operate said shaking means.

7. In a detector for ether-waves, the combination of a tube, insulating-blocks in said tube, metallic powder between said blocks, a circuit through said powder, lneans in said tube supported by said blocks for shaking the powder, and means to operate said shaking means.

8. In a detector forV ether-waves, the combination of a tube, insulating-blocks in said tube, metallic powder between said blocks, a circuit through said powder, a magnetic vibrator in saidftube supported by said blocks, and an electromagnet actuated by the circuit to operate said vibrator to shake the powder.

9. In a detector for ether-waves, the coinbination of a tube, L-shaped insulating-blocks in-said tube, metallic plates secured to said blocks, metallic powder between said plates, a circuit through said plates. and said powder, a magnetic body supported on said blocks above said powder, and an electromagnet actuated by the circuit to move said body, and thereby shake the powder.

lO. In a system of ether-wave telegraphy, the combination of an emitting apparatus, and a receiving apparatus, the latter coinprising a receiving-circuit including a coherer, a main circuit in parallel with said coherer, a relay-circuit controlled by said main circuit, a signaling-relay therein, and means controlled by said relay-circuit to render said signaling-relay active between the impulses impressed on said relay-circuit.

1l. A receiving apparatus for ether-wave telegraphy comprising a receiving-circuit including a coherer, a main circuit in parallel with said coherer, a relay in said main circuit, a second circuit controlled by said relay, a signaling-relay in said second circuit, and means controlled by said second circuit to render said signaling-relay active between the impulses impressed on said relaycircuit.

12. A receiving` apparatus for ether-wave telegraphy comprising a receiving-circuit, including a coherer, a main circuit in parallel with said coherer, a relay in said main circuit, a second circuit controlled by said relay, a compound relay having its main coil in said second circuit and its auxiliary. coil in circuit with a condenser, whereby said auxiliary coil is energized by the condenserdischarge during the intervals between impulses.

13. A receiving apparatus for ether-wave telegraphy comprising a receiving-circuit, including a coherer, a main circuit in parallel with said coherer, a relay in said main circuit, a second circuit controlled by said relay, a compound relay having its main coil in said' second circuit and its auxiliarycoil in circuit with a condenser, whereby said auxiliary coil is energized by the condenserdischarge during the intervals between impulses, an additional relay, a circuit therefor controlled by said compound relay, a receiver and circuit actuating the same controlled by said additional relay.

In testimony whereof I aix my signature in presence of two witnesses.

HARRY SHOEMAKER. Witnessesf G. V. GEI-Inmo, R. LEAMAN.

IOO 

